<?php
	session_start();  //必须处在脚本最顶端

	$table = array(
		'1' => '狗',
		'2' => '猫',
		'3' => '鱼',
		'4' => '鸟',
		);

	$index = rand(1,4);

	$value = $table[$index];

	$_SESSION['authcode'] = $value;


	$filename = dirname(__FILE__) . '\\' . $index . '.jpg';

	$content = file_get_contents($filename);

	header("Content-type:image/jpg;charset=UTF8");

	echo $content;

